The push pin is a fastener commonly utilized by the automotive industry to affix plastic parts such as a trim panel to a substrate such as a sheet metal panel. Thus, for example, a push pin may be utilized as an attachment means for securing a door trim panel to an inner sheet metal panel. As illustrated in FIG. 1, the trim panel T incorporates a “doghouse” feature D to hold the push pin P in position on the trim panel as the trim panel is connected to the underlying substrate or sheet metal panel S.
A special element is needed in the trim panel mold in order to create the doghouse feature. That special element, known as a “lifter” is an internal action in the mold that allows one to mold the plastic features that are not open to normal core/cavity die draw direction. A mold that incorporates a “lifter” may require an increase in investment capital on the order of 10% to 15% per action depending on the complexity. Thus, a mold that incorporates a lifter requires a substantial additional capital investment.
It should be further appreciated that such a lifter needs a minimum distance “A” for the steel of the mold not to overheat, break or wear out. See FIG. 2. This distance is 6.5 mm. Added to this, the minimum distance required to set up the push pin to sheet metal connection is “B”, a distance of 9.5 mm. Thus, a prior art trim panel T incorporating a push pin P using a traditional doghouse feature D requires a minimum distance C of 16 mm from flange to sheet metal. This minimum clearance distance C represents a significant limitation for vehicle designers.
This document relates to a new and improved trim panel mounting system which eliminates the traditional doghouse feature and, thus, the need for a “lifter” in the trim panel mold. Thus, the new trim panel mounting system reduces capital investment for the mold. Further, it also reduces the necessary clearance required for a push pin connection between the trim panel and the sheet metal panel/substrate to as little as 12 mm or less: that is, approximately a 25% reduction in clearance requirement from the traditional 16 mm clearance as illustrated in FIG. 2. Thus, the proposed trim panel mounting system represents a significant advance in the art.